
/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_http.h>

#if (NGX_HTTP_V2 && T_NGX_HTTP2_SRV_ENABLE)
#include <ngx_http_v2_module.h>
#endif

typedef ngx_int_t (*ngx_ssl_variable_handler_pt)(ngx_connection_t *c,
                                                 ngx_pool_t       *pool,
                                                 ngx_str_t        *s);


#define NGX_DEFAULT_CIPHERS    "HIGH:!aNULL:!MD5"
#define NGX_DEFAULT_ECDH_CURVE "auto"

#define NGX_HTTP_NPN_ADVERTISE "\x08http/1.1"


#ifdef TLSEXT_TYPE_application_layer_protocol_negotiation
static int ngx_http_ssl_alpn_select(ngx_ssl_conn_t       *ssl_conn,
                                    const unsigned char **out,
                                    unsigned char        *outlen,
                                    const unsigned char *in, unsigned int inlen,
                                    void *arg);
#endif

#ifdef TLSEXT_TYPE_next_proto_neg
static int ngx_http_ssl_npn_advertised(ngx_ssl_conn_t       *ssl_conn,
                                       const unsigned char **out,
                                       unsigned int *outlen, void *arg);
#endif

static ngx_int_t ngx_http_ssl_static_variable(ngx_http_request_t        *r,
                                              ngx_http_variable_value_t *v,
                                              uintptr_t                  data);
static ngx_int_t ngx_http_ssl_variable(ngx_http_request_t        *r,
                                       ngx_http_variable_value_t *v,
                                       uintptr_t                  data);

static ngx_int_t ngx_http_ssl_add_variables(ngx_conf_t *cf);
static void     *ngx_http_ssl_create_srv_conf(ngx_conf_t *cf);
#if (T_NGX_HTTP_SSL_VCE)
static void *ngx_http_ssl_create_loc_conf(ngx_conf_t *cf);
#endif
static char *ngx_http_ssl_merge_srv_conf(ngx_conf_t *cf, void *parent,
                                         void *child);

static ngx_int_t
ngx_http_ssl_compile_certificates(ngx_conf_t              *cf,
                                  ngx_http_ssl_srv_conf_t *conf);

static char *ngx_http_ssl_enable(ngx_conf_t *cf, ngx_command_t *cmd,
                                 void *conf);
#if (NGX_HTTP_SSL && NGX_SSL_ASYNC)
static char *ngx_http_ssl_enable_async(ngx_conf_t *cf, ngx_command_t *cmd,
                                       void *conf);
#endif
static char *ngx_http_ssl_password_file(ngx_conf_t *cf, ngx_command_t *cmd,
                                        void *conf);
static char *ngx_http_ssl_session_cache(ngx_conf_t *cf, ngx_command_t *cmd,
                                        void *conf);

static ngx_int_t ngx_http_ssl_init(ngx_conf_t *cf);


static ngx_conf_bitmask_t ngx_http_ssl_protocols[] = {
    {ngx_string("SSLv2"), NGX_SSL_SSLv2},
    {ngx_string("SSLv3"), NGX_SSL_SSLv3},
    {ngx_string("TLSv1"), NGX_SSL_TLSv1},
    {ngx_string("TLSv1.1"), NGX_SSL_TLSv1_1},
    {ngx_string("TLSv1.2"), NGX_SSL_TLSv1_2},
    {ngx_string("TLSv1.3"), NGX_SSL_TLSv1_3},
    {ngx_null_string, 0}};


static ngx_conf_enum_t ngx_http_ssl_verify[] = {
    {ngx_string("off"), 0},
    {ngx_string("on"), 1},
    {ngx_string("optional"), 2},
    {ngx_string("optional_no_ca"), 3},
    {ngx_null_string, 0}};


static ngx_conf_deprecated_t ngx_http_ssl_deprecated = {
    ngx_conf_deprecated, "ssl", "listen ... ssl"};


static ngx_command_t ngx_http_ssl_commands[] = {

    {ngx_string("ssl"), NGX_HTTP_MAIN_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_FLAG,
     ngx_http_ssl_enable, NGX_HTTP_SRV_CONF_OFFSET,
     offsetof(ngx_http_ssl_srv_conf_t, enable), &ngx_http_ssl_deprecated},

#if (NGX_HTTP_SSL && NGX_SSL_ASYNC)
    {ngx_string("ssl_async"),
     NGX_HTTP_MAIN_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_FLAG,
     ngx_http_ssl_enable_async, NGX_HTTP_SRV_CONF_OFFSET,
     offsetof(ngx_http_ssl_srv_conf_t, async_enable), NULL},
#endif

    {ngx_string("ssl_certificate"),
     NGX_HTTP_MAIN_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_TAKE1,
     ngx_conf_set_str_array_slot, NGX_HTTP_SRV_CONF_OFFSET,
     offsetof(ngx_http_ssl_srv_conf_t, certificates), NULL},

    {ngx_string("ssl_certificate_key"),
     NGX_HTTP_MAIN_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_TAKE1,
     ngx_conf_set_str_array_slot, NGX_HTTP_SRV_CONF_OFFSET,
     offsetof(ngx_http_ssl_srv_conf_t, certificate_keys), NULL},

    {ngx_string("ssl_password_file"),
     NGX_HTTP_MAIN_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_TAKE1,
     ngx_http_ssl_password_file, NGX_HTTP_SRV_CONF_OFFSET, 0, NULL},

    {ngx_string("ssl_dhparam"),
     NGX_HTTP_MAIN_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_TAKE1,
     ngx_conf_set_str_slot, NGX_HTTP_SRV_CONF_OFFSET,
     offsetof(ngx_http_ssl_srv_conf_t, dhparam), NULL},

    {ngx_string("ssl_ecdh_curve"),
     NGX_HTTP_MAIN_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_TAKE1,
     ngx_conf_set_str_slot, NGX_HTTP_SRV_CONF_OFFSET,
     offsetof(ngx_http_ssl_srv_conf_t, ecdh_curve), NULL},

    {ngx_string("ssl_protocols"),
     NGX_HTTP_MAIN_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_1MORE,
     ngx_conf_set_bitmask_slot, NGX_HTTP_SRV_CONF_OFFSET,
     offsetof(ngx_http_ssl_srv_conf_t, protocols), &ngx_http_ssl_protocols},

    {ngx_string("ssl_ciphers"),
     NGX_HTTP_MAIN_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_TAKE1,
     ngx_conf_set_str_slot, NGX_HTTP_SRV_CONF_OFFSET,
     offsetof(ngx_http_ssl_srv_conf_t, ciphers), NULL},

    {ngx_string("ssl_buffer_size"),
     NGX_HTTP_MAIN_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_TAKE1,
     ngx_conf_set_size_slot, NGX_HTTP_SRV_CONF_OFFSET,
     offsetof(ngx_http_ssl_srv_conf_t, buffer_size), NULL},

    {ngx_string("ssl_verify_client"),
     NGX_HTTP_MAIN_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_TAKE1,
     ngx_conf_set_enum_slot, NGX_HTTP_SRV_CONF_OFFSET,
     offsetof(ngx_http_ssl_srv_conf_t, verify), &ngx_http_ssl_verify},

#if (T_NGX_HTTP_SSL_VCE)
    {ngx_string("ssl_verify_client_exception"),
     NGX_HTTP_LOC_CONF | NGX_CONF_TAKE1, ngx_conf_set_flag_slot,
     NGX_HTTP_LOC_CONF_OFFSET,
     offsetof(ngx_http_ssl_loc_conf_t, verify_exception), NULL},
#endif

    {ngx_string("ssl_verify_depth"),
     NGX_HTTP_MAIN_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_TAKE1,
     ngx_conf_set_num_slot, NGX_HTTP_SRV_CONF_OFFSET,
     offsetof(ngx_http_ssl_srv_conf_t, verify_depth), NULL},

    {ngx_string("ssl_client_certificate"),
     NGX_HTTP_MAIN_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_TAKE1,
     ngx_conf_set_str_slot, NGX_HTTP_SRV_CONF_OFFSET,
     offsetof(ngx_http_ssl_srv_conf_t, client_certificate), NULL},

    {ngx_string("ssl_trusted_certificate"),
     NGX_HTTP_MAIN_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_TAKE1,
     ngx_conf_set_str_slot, NGX_HTTP_SRV_CONF_OFFSET,
     offsetof(ngx_http_ssl_srv_conf_t, trusted_certificate), NULL},

    {ngx_string("ssl_prefer_server_ciphers"),
     NGX_HTTP_MAIN_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_FLAG,
     ngx_conf_set_flag_slot, NGX_HTTP_SRV_CONF_OFFSET,
     offsetof(ngx_http_ssl_srv_conf_t, prefer_server_ciphers), NULL},

    {ngx_string("ssl_session_cache"),
     NGX_HTTP_MAIN_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_TAKE12,
     ngx_http_ssl_session_cache, NGX_HTTP_SRV_CONF_OFFSET, 0, NULL},

    {ngx_string("ssl_session_tickets"),
     NGX_HTTP_MAIN_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_FLAG,
     ngx_conf_set_flag_slot, NGX_HTTP_SRV_CONF_OFFSET,
     offsetof(ngx_http_ssl_srv_conf_t, session_tickets), NULL},

    {ngx_string("ssl_session_ticket_key"),
     NGX_HTTP_MAIN_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_TAKE1,
     ngx_conf_set_str_array_slot, NGX_HTTP_SRV_CONF_OFFSET,
     offsetof(ngx_http_ssl_srv_conf_t, session_ticket_keys), NULL},

    {ngx_string("ssl_session_timeout"),
     NGX_HTTP_MAIN_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_TAKE1,
     ngx_conf_set_sec_slot, NGX_HTTP_SRV_CONF_OFFSET,
     offsetof(ngx_http_ssl_srv_conf_t, session_timeout), NULL},

    {ngx_string("ssl_crl"),
     NGX_HTTP_MAIN_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_TAKE1,
     ngx_conf_set_str_slot, NGX_HTTP_SRV_CONF_OFFSET,
     offsetof(ngx_http_ssl_srv_conf_t, crl), NULL},

    {ngx_string("ssl_stapling"),
     NGX_HTTP_MAIN_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_FLAG,
     ngx_conf_set_flag_slot, NGX_HTTP_SRV_CONF_OFFSET,
     offsetof(ngx_http_ssl_srv_conf_t, stapling), NULL},

    {ngx_string("ssl_stapling_file"),
     NGX_HTTP_MAIN_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_TAKE1,
     ngx_conf_set_str_slot, NGX_HTTP_SRV_CONF_OFFSET,
     offsetof(ngx_http_ssl_srv_conf_t, stapling_file), NULL},

    {ngx_string("ssl_stapling_responder"),
     NGX_HTTP_MAIN_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_TAKE1,
     ngx_conf_set_str_slot, NGX_HTTP_SRV_CONF_OFFSET,
     offsetof(ngx_http_ssl_srv_conf_t, stapling_responder), NULL},

    {ngx_string("ssl_stapling_verify"),
     NGX_HTTP_MAIN_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_FLAG,
     ngx_conf_set_flag_slot, NGX_HTTP_SRV_CONF_OFFSET,
     offsetof(ngx_http_ssl_srv_conf_t, stapling_verify), NULL},

    {ngx_string("ssl_early_data"),
     NGX_HTTP_MAIN_CONF | NGX_HTTP_SRV_CONF | NGX_CONF_FLAG,
     ngx_conf_set_flag_slot, NGX_HTTP_SRV_CONF_OFFSET,
     offsetof(ngx_http_ssl_srv_conf_t, early_data), NULL},

    ngx_null_command};


static ngx_http_module_t ngx_http_ssl_module_ctx = {
    ngx_http_ssl_add_variables, /* preconfiguration */
    ngx_http_ssl_init,          /* postconfiguration */

    NULL, /* create main configuration */
    NULL, /* init main configuration */

    ngx_http_ssl_create_srv_conf, /* create server configuration */
    ngx_http_ssl_merge_srv_conf,  /* merge server configuration */

#if (T_NGX_HTTP_SSL_VCE)
    ngx_http_ssl_create_loc_conf, /* create location configuration */
#else
    NULL, /* create location configuration */
#endif
    NULL /* merge location configuration */
};


ngx_module_t ngx_http_ssl_module = {
    NGX_MODULE_V1,
    &ngx_http_ssl_module_ctx, /* module context */
    ngx_http_ssl_commands,    /* module directives */
    NGX_HTTP_MODULE,          /* module type */
    NULL,                     /* init master */
    NULL,                     /* init module */
    NULL,                     /* init process */
    NULL,                     /* init thread */
    NULL,                     /* exit thread */
    NULL,                     /* exit process */
    NULL,                     /* exit master */
    NGX_MODULE_V1_PADDING};


static ngx_http_variable_t ngx_http_ssl_vars[] = {

    {ngx_string("ssl_protocol"), NULL, ngx_http_ssl_static_variable,
     (uintptr_t)ngx_ssl_get_protocol, NGX_HTTP_VAR_CHANGEABLE, 0},

    {ngx_string("ssl_cipher"), NULL, ngx_http_ssl_static_variable,
     (uintptr_t)ngx_ssl_get_cipher_name, NGX_HTTP_VAR_CHANGEABLE, 0},

    {ngx_string("ssl_ciphers"), NULL, ngx_http_ssl_variable,
     (uintptr_t)ngx_ssl_get_ciphers, NGX_HTTP_VAR_CHANGEABLE, 0},

    {ngx_string("ssl_curves"), NULL, ngx_http_ssl_variable,
     (uintptr_t)ngx_ssl_get_curves, NGX_HTTP_VAR_CHANGEABLE, 0},

    {ngx_string("ssl_session_id"), NULL, ngx_http_ssl_variable,
     (uintptr_t)ngx_ssl_get_session_id, NGX_HTTP_VAR_CHANGEABLE, 0},

    {ngx_string("ssl_session_reused"), NULL, ngx_http_ssl_variable,
     (uintptr_t)ngx_ssl_get_session_reused, NGX_HTTP_VAR_CHANGEABLE, 0},

    {ngx_string("ssl_early_data"), NULL, ngx_http_ssl_variable,
     (uintptr_t)ngx_ssl_get_early_data,
     NGX_HTTP_VAR_CHANGEABLE | NGX_HTTP_VAR_NOCACHEABLE, 0},

    {ngx_string("ssl_server_name"), NULL, ngx_http_ssl_variable,
     (uintptr_t)ngx_ssl_get_server_name, NGX_HTTP_VAR_CHANGEABLE, 0},

    {ngx_string("ssl_client_cert"), NULL, ngx_http_ssl_variable,
     (uintptr_t)ngx_ssl_get_certificate, NGX_HTTP_VAR_CHANGEABLE, 0},

    {ngx_string("ssl_client_raw_cert"), NULL, ngx_http_ssl_variable,
     (uintptr_t)ngx_ssl_get_raw_certificate, NGX_HTTP_VAR_CHANGEABLE, 0},

    {ngx_string("ssl_client_escaped_cert"), NULL, ngx_http_ssl_variable,
     (uintptr_t)ngx_ssl_get_escaped_certificate, NGX_HTTP_VAR_CHANGEABLE, 0},

    {ngx_string("ssl_client_s_dn"), NULL, ngx_http_ssl_variable,
     (uintptr_t)ngx_ssl_get_subject_dn, NGX_HTTP_VAR_CHANGEABLE, 0},

    {ngx_string("ssl_client_i_dn"), NULL, ngx_http_ssl_variable,
     (uintptr_t)ngx_ssl_get_issuer_dn, NGX_HTTP_VAR_CHANGEABLE, 0},

    {ngx_string("ssl_client_s_dn_legacy"), NULL, ngx_http_ssl_variable,
     (uintptr_t)ngx_ssl_get_subject_dn_legacy, NGX_HTTP_VAR_CHANGEABLE, 0},

    {ngx_string("ssl_client_i_dn_legacy"), NULL, ngx_http_ssl_variable,
     (uintptr_t)ngx_ssl_get_issuer_dn_legacy, NGX_HTTP_VAR_CHANGEABLE, 0},

    {ngx_string("ssl_client_serial"), NULL, ngx_http_ssl_variable,
     (uintptr_t)ngx_ssl_get_serial_number, NGX_HTTP_VAR_CHANGEABLE, 0},

    {ngx_string("ssl_client_fingerprint"), NULL, ngx_http_ssl_variable,
     (uintptr_t)ngx_ssl_get_fingerprint, NGX_HTTP_VAR_CHANGEABLE, 0},

    {ngx_string("ssl_client_verify"), NULL, ngx_http_ssl_variable,
     (uintptr_t)ngx_ssl_get_client_verify, NGX_HTTP_VAR_CHANGEABLE, 0},

    {ngx_string("ssl_client_v_start"), NULL, ngx_http_ssl_variable,
     (uintptr_t)ngx_ssl_get_client_v_start, NGX_HTTP_VAR_CHANGEABLE, 0},

    {ngx_string("ssl_client_v_end"), NULL, ngx_http_ssl_variable,
     (uintptr_t)ngx_ssl_get_client_v_end, NGX_HTTP_VAR_CHANGEABLE, 0},

    {ngx_string("ssl_client_v_remain"), NULL, ngx_http_ssl_variable,
     (uintptr_t)ngx_ssl_get_client_v_remain, NGX_HTTP_VAR_CHANGEABLE, 0},

#if (T_NGX_SSL_HANDSHAKE_TIME)
    /* $ssl_shandshakd_time deprecated and will be removed in the next release
     */
    {ngx_string("ssl_handshakd_time"), NULL, ngx_http_ssl_variable,
     (uintptr_t)ngx_ssl_get_handshake_time, NGX_HTTP_VAR_CHANGEABLE, 0},

    {ngx_string("ssl_handshake_time"), NULL, ngx_http_ssl_variable,
     (uintptr_t)ngx_ssl_get_handshake_time, NGX_HTTP_VAR_CHANGEABLE, 0},

    {ngx_string("ssl_handshake_time_msec"), NULL, ngx_http_ssl_variable,
     (uintptr_t)ngx_ssl_get_handshake_time_msec, NGX_HTTP_VAR_CHANGEABLE, 0},
#endif

    ngx_http_null_variable};


static ngx_str_t ngx_http_ssl_sess_id_ctx = ngx_string("HTTP");


#ifdef TLSEXT_TYPE_application_layer_protocol_negotiation

static int
ngx_http_ssl_alpn_select(ngx_ssl_conn_t *ssl_conn, const unsigned char **out,
                         unsigned char *outlen, const unsigned char *in,
                         unsigned int inlen, void *arg)
{
    unsigned int   srvlen;
    unsigned char *srv;
#if (NGX_DEBUG)
    unsigned int i;
#endif
#if (NGX_HTTP_V2)
    ngx_http_connection_t *hc;
#if (T_NGX_HTTP2_SRV_ENABLE)
    ngx_http_v2_srv_conf_t *h2scf;
#endif
#endif
#if (NGX_HTTP_V2 || NGX_DEBUG)
    ngx_connection_t *c;

    c = ngx_ssl_get_connection(ssl_conn);
#endif

#if (NGX_DEBUG)
    for (i = 0; i < inlen; i += in[i] + 1)
    {
        ngx_log_debug2(NGX_LOG_DEBUG_HTTP, c->log, 0,
                       "SSL ALPN supported by client: %*s", (size_t)in[i],
                       &in[i + 1]);
    }
#endif

#if (NGX_HTTP_V2)
    hc = c->data;

#if (T_NGX_HTTP2_SRV_ENABLE)
    h2scf = ngx_http_get_module_srv_conf(hc->conf_ctx, ngx_http_v2_module);
#endif

    if (
#if (T_NGX_HTTP2_SRV_ENABLE)
        (
#endif
            hc->addr_conf->http2
#if (T_NGX_HTTP2_SRV_ENABLE)
            && h2scf->enable != 0)
        || h2scf->enable == 1
#endif
    )
    {
        srv =
            (unsigned char *)NGX_HTTP_V2_ALPN_ADVERTISE NGX_HTTP_NPN_ADVERTISE;
        srvlen = sizeof(NGX_HTTP_V2_ALPN_ADVERTISE NGX_HTTP_NPN_ADVERTISE) - 1;
    }
    else
#endif
    {
        srv    = (unsigned char *)NGX_HTTP_NPN_ADVERTISE;
        srvlen = sizeof(NGX_HTTP_NPN_ADVERTISE) - 1;
    }

    if (SSL_select_next_proto((unsigned char **)out, outlen, srv, srvlen, in,
                              inlen)
        != OPENSSL_NPN_NEGOTIATED)
    {
        return SSL_TLSEXT_ERR_NOACK;
    }

    ngx_log_debug2(NGX_LOG_DEBUG_HTTP, c->log, 0, "SSL ALPN selected: %*s",
                   (size_t)*outlen, *out);

    return SSL_TLSEXT_ERR_OK;
}

#endif


#ifdef TLSEXT_TYPE_next_proto_neg

static int
ngx_http_ssl_npn_advertised(ngx_ssl_conn_t *ssl_conn, const unsigned char **out,
                            unsigned int *outlen, void *arg)
{
#if (NGX_HTTP_V2 || NGX_DEBUG)
    ngx_connection_t *c;

    c = ngx_ssl_get_connection(ssl_conn);
    ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0, "SSL NPN advertised");
#endif

#if (NGX_HTTP_V2)
    {
        ngx_http_connection_t *hc;
#if (T_NGX_HTTP2_SRV_ENABLE)
        ngx_http_v2_srv_conf_t *h2scf;
#endif

        hc = c->data;

#if (T_NGX_HTTP2_SRV_ENABLE)
        h2scf = ngx_http_get_module_srv_conf(hc->conf_ctx, ngx_http_v2_module);
#endif

        if (
#if (T_NGX_HTTP2_SRV_ENABLE)
            (
#endif
                hc->addr_conf->http2
#if (T_NGX_HTTP2_SRV_ENABLE)
                && h2scf->enable != 0)
            || h2scf->enable == 1
#endif
        )
        {
            *out = (unsigned char *)
                NGX_HTTP_V2_NPN_ADVERTISE NGX_HTTP_NPN_ADVERTISE;
            *outlen =
                sizeof(NGX_HTTP_V2_NPN_ADVERTISE NGX_HTTP_NPN_ADVERTISE) - 1;

            return SSL_TLSEXT_ERR_OK;
        }
    }
#endif

    *out    = (unsigned char *)NGX_HTTP_NPN_ADVERTISE;
    *outlen = sizeof(NGX_HTTP_NPN_ADVERTISE) - 1;

    return SSL_TLSEXT_ERR_OK;
}

#endif


static ngx_int_t
ngx_http_ssl_static_variable(ngx_http_request_t        *r,
                             ngx_http_variable_value_t *v, uintptr_t data)
{
    ngx_ssl_variable_handler_pt handler = (ngx_ssl_variable_handler_pt)data;

    size_t    len;
    ngx_str_t s;

    if (r->connection->ssl)
    {
        (void)handler(r->connection, NULL, &s);

        v->data = s.data;

        for (len = 0; v->data[len]; len++)
        { /* void */
        }

        v->len          = len;
        v->valid        = 1;
        v->no_cacheable = 0;
        v->not_found    = 0;

        return NGX_OK;
    }

    v->not_found = 1;

    return NGX_OK;
}


static ngx_int_t
ngx_http_ssl_variable(ngx_http_request_t *r, ngx_http_variable_value_t *v,
                      uintptr_t data)
{
    ngx_ssl_variable_handler_pt handler = (ngx_ssl_variable_handler_pt)data;

    ngx_str_t s;

    if (r->connection->ssl)
    {
        if (handler(r->connection, r->pool, &s) != NGX_OK)
        {
            return NGX_ERROR;
        }

        v->len  = s.len;
        v->data = s.data;

        if (v->len)
        {
            v->valid        = 1;
            v->no_cacheable = 0;
            v->not_found    = 0;

            return NGX_OK;
        }
    }

    v->not_found = 1;

    return NGX_OK;
}


static ngx_int_t
ngx_http_ssl_add_variables(ngx_conf_t *cf)
{
    ngx_http_variable_t *var, *v;

    for (v = ngx_http_ssl_vars; v->name.len; v++)
    {
        var = ngx_http_add_variable(cf, &v->name, v->flags);
        if (var == NULL)
        {
            return NGX_ERROR;
        }

        var->get_handler = v->get_handler;
        var->data        = v->data;
    }

    return NGX_OK;
}


static void *
ngx_http_ssl_create_srv_conf(ngx_conf_t *cf)
{
    ngx_http_ssl_srv_conf_t *sscf;

    sscf = ngx_pcalloc(cf->pool, sizeof(ngx_http_ssl_srv_conf_t));
    if (sscf == NULL)
    {
        return NULL;
    }

    /*
     * set by ngx_pcalloc():
     *
     *     sscf->protocols = 0;
     *     sscf->certificate_values = NULL;
     *     sscf->dhparam = { 0, NULL };
     *     sscf->ecdh_curve = { 0, NULL };
     *     sscf->client_certificate = { 0, NULL };
     *     sscf->trusted_certificate = { 0, NULL };
     *     sscf->crl = { 0, NULL };
     *     sscf->ciphers = { 0, NULL };
     *     sscf->shm_zone = NULL;
     *     sscf->stapling_file = { 0, NULL };
     *     sscf->stapling_responder = { 0, NULL };
     */

    sscf->enable = NGX_CONF_UNSET;
#if (NGX_HTTP_SSL && NGX_SSL_ASYNC)
    sscf->async_enable = NGX_CONF_UNSET;
#endif
    sscf->prefer_server_ciphers = NGX_CONF_UNSET;
    sscf->early_data            = NGX_CONF_UNSET;
    sscf->buffer_size           = NGX_CONF_UNSET_SIZE;
    sscf->verify                = NGX_CONF_UNSET_UINT;
    sscf->verify_depth          = NGX_CONF_UNSET_UINT;
    sscf->certificates          = NGX_CONF_UNSET_PTR;
    sscf->certificate_keys      = NGX_CONF_UNSET_PTR;
    sscf->passwords             = NGX_CONF_UNSET_PTR;
    sscf->builtin_session_cache = NGX_CONF_UNSET;
    sscf->session_timeout       = NGX_CONF_UNSET;
    sscf->session_tickets       = NGX_CONF_UNSET;
    sscf->session_ticket_keys   = NGX_CONF_UNSET_PTR;
    sscf->stapling              = NGX_CONF_UNSET;
    sscf->stapling_verify       = NGX_CONF_UNSET;

    return sscf;
}


#if (T_NGX_HTTP_SSL_VCE)
static void *
ngx_http_ssl_create_loc_conf(ngx_conf_t *cf)
{
    ngx_http_ssl_loc_conf_t *slcf;

    slcf = ngx_pcalloc(cf->pool, sizeof(ngx_http_ssl_loc_conf_t));
    if (slcf == NULL)
    {
        return NULL;
    }

    slcf->verify_exception = NGX_CONF_UNSET;

    return slcf;
}
#endif


static char *
ngx_http_ssl_merge_srv_conf(ngx_conf_t *cf, void *parent, void *child)
{
    ngx_http_ssl_srv_conf_t *prev = parent;
    ngx_http_ssl_srv_conf_t *conf = child;

    ngx_pool_cleanup_t *cln;

    if (conf->enable == NGX_CONF_UNSET)
    {
        if (prev->enable == NGX_CONF_UNSET)
        {
            conf->enable = 0;
        }
        else
        {
            conf->enable = prev->enable;
            conf->file   = prev->file;
            conf->line   = prev->line;
        }
    }

#if (NGX_HTTP_SSL && NGX_SSL_ASYNC)
    if (conf->async_enable == NGX_CONF_UNSET)
    {
        if (prev->async_enable == NGX_CONF_UNSET)
        {
            conf->async_enable = 0;
        }
        else
        {
            conf->async_enable = prev->async_enable;
            conf->file         = prev->file;
            conf->line         = prev->line;
        }
    }
#endif
    ngx_conf_merge_value(conf->session_timeout, prev->session_timeout, 300);

    ngx_conf_merge_value(conf->prefer_server_ciphers,
                         prev->prefer_server_ciphers, 0);

    ngx_conf_merge_value(conf->early_data, prev->early_data, 0);

    ngx_conf_merge_bitmask_value(conf->protocols, prev->protocols,
                                 (NGX_CONF_BITMASK_SET | NGX_SSL_TLSv1
                                  | NGX_SSL_TLSv1_1 | NGX_SSL_TLSv1_2));

    ngx_conf_merge_size_value(conf->buffer_size, prev->buffer_size,
                              NGX_SSL_BUFSIZE);

    ngx_conf_merge_uint_value(conf->verify, prev->verify, 0);
    ngx_conf_merge_uint_value(conf->verify_depth, prev->verify_depth, 1);

    ngx_conf_merge_ptr_value(conf->certificates, prev->certificates, NULL);
    ngx_conf_merge_ptr_value(conf->certificate_keys, prev->certificate_keys,
                             NULL);

    ngx_conf_merge_ptr_value(conf->passwords, prev->passwords, NULL);

    ngx_conf_merge_str_value(conf->dhparam, prev->dhparam, "");

    ngx_conf_merge_str_value(conf->client_certificate, prev->client_certificate,
                             "");
    ngx_conf_merge_str_value(conf->trusted_certificate,
                             prev->trusted_certificate, "");
    ngx_conf_merge_str_value(conf->crl, prev->crl, "");

    ngx_conf_merge_str_value(conf->ecdh_curve, prev->ecdh_curve,
                             NGX_DEFAULT_ECDH_CURVE);

    ngx_conf_merge_str_value(conf->ciphers, prev->ciphers, NGX_DEFAULT_CIPHERS);

    ngx_conf_merge_value(conf->stapling, prev->stapling, 0);
    ngx_conf_merge_value(conf->stapling_verify, prev->stapling_verify, 0);
    ngx_conf_merge_str_value(conf->stapling_file, prev->stapling_file, "");
    ngx_conf_merge_str_value(conf->stapling_responder, prev->stapling_responder,
                             "");

    conf->ssl.log = cf->log;

    if (conf->enable)
    {
        if (conf->certificates == NULL)
        {
            ngx_log_error(NGX_LOG_EMERG, cf->log, 0,
                          "no \"ssl_certificate\" is defined for "
                          "the \"ssl\" directive in %s:%ui",
                          conf->file, conf->line);
            return NGX_CONF_ERROR;
        }

        if (conf->certificate_keys == NULL)
        {
            ngx_log_error(NGX_LOG_EMERG, cf->log, 0,
                          "no \"ssl_certificate_key\" is defined for "
                          "the \"ssl\" directive in %s:%ui",
                          conf->file, conf->line);
            return NGX_CONF_ERROR;
        }
#if (NGX_HTTP_SSL && NGX_SSL_ASYNC)
        conf->ssl.async_enable = conf->async_enable;
#endif

        if (conf->certificate_keys->nelts < conf->certificates->nelts)
        {
            ngx_log_error(NGX_LOG_EMERG, cf->log, 0,
                          "no \"ssl_certificate_key\" is defined "
                          "for certificate \"%V\" and "
                          "the \"ssl\" directive in %s:%ui",
                          ((ngx_str_t *)conf->certificates->elts)
                              + conf->certificates->nelts - 1,
                          conf->file, conf->line);
            return NGX_CONF_ERROR;
        }
    }
    else
    {
        if (conf->certificates == NULL)
        {
            return NGX_CONF_OK;
        }

        if (conf->certificate_keys == NULL
            || conf->certificate_keys->nelts < conf->certificates->nelts)
        {
            ngx_log_error(NGX_LOG_EMERG, cf->log, 0,
                          "no \"ssl_certificate_key\" is defined "
                          "for certificate \"%V\"",
                          ((ngx_str_t *)conf->certificates->elts)
                              + conf->certificates->nelts - 1);
            return NGX_CONF_ERROR;
        }
    }

    if (ngx_ssl_create(&conf->ssl, conf->protocols, conf) != NGX_OK)
    {
        return NGX_CONF_ERROR;
    }

    cln = ngx_pool_cleanup_add(cf->pool, 0);
    if (cln == NULL)
    {
        ngx_ssl_cleanup_ctx(&conf->ssl);
        return NGX_CONF_ERROR;
    }

    cln->handler = ngx_ssl_cleanup_ctx;
    cln->data    = &conf->ssl;

#ifdef SSL_CTRL_SET_TLSEXT_HOSTNAME

    if (SSL_CTX_set_tlsext_servername_callback(conf->ssl.ctx,
                                               ngx_http_ssl_servername)
        == 0)
    {
        ngx_log_error(
            NGX_LOG_WARN, cf->log, 0,
            "nginx was built with SNI support, however, now it is linked "
            "dynamically to an OpenSSL library which has no tlsext support, "
            "therefore SNI is not available");
    }

#endif

#ifdef TLSEXT_TYPE_application_layer_protocol_negotiation
    SSL_CTX_set_alpn_select_cb(conf->ssl.ctx, ngx_http_ssl_alpn_select, NULL);
#endif

#ifdef TLSEXT_TYPE_next_proto_neg
    SSL_CTX_set_next_protos_advertised_cb(conf->ssl.ctx,
                                          ngx_http_ssl_npn_advertised, NULL);
#endif

    if (ngx_http_ssl_compile_certificates(cf, conf) != NGX_OK)
    {
        return NGX_CONF_ERROR;
    }

    if (conf->certificate_values)
    {
#ifdef SSL_R_CERT_CB_ERROR

        /* install callback to lookup certificates */

        SSL_CTX_set_cert_cb(conf->ssl.ctx, ngx_http_ssl_certificate, conf);

#else
        ngx_log_error(NGX_LOG_EMERG, cf->log, 0,
                      "variables in "
                      "\"ssl_certificate\" and \"ssl_certificate_key\" "
                      "directives are not supported on this platform");
        return NGX_CONF_ERROR;
#endif
    }
    else
    {
        /* configure certificates */

        if (ngx_ssl_certificates(cf, &conf->ssl, conf->certificates,
                                 conf->certificate_keys, conf->passwords)
            != NGX_OK)
        {
            return NGX_CONF_ERROR;
        }
    }

    if (ngx_ssl_ciphers(cf, &conf->ssl, &conf->ciphers,
                        conf->prefer_server_ciphers)
        != NGX_OK)
    {
        return NGX_CONF_ERROR;
    }

    conf->ssl.buffer_size = conf->buffer_size;

    if (conf->verify)
    {
        if (conf->client_certificate.len == 0 && conf->verify != 3)
        {
            ngx_log_error(NGX_LOG_EMERG, cf->log, 0,
                          "no ssl_client_certificate for ssl_verify_client");
            return NGX_CONF_ERROR;
        }

        if (ngx_ssl_client_certificate(
                cf, &conf->ssl, &conf->client_certificate, conf->verify_depth)
            != NGX_OK)
        {
            return NGX_CONF_ERROR;
        }
    }

    if (ngx_ssl_trusted_certificate(cf, &conf->ssl, &conf->trusted_certificate,
                                    conf->verify_depth)
        != NGX_OK)
    {
        return NGX_CONF_ERROR;
    }

    if (ngx_ssl_crl(cf, &conf->ssl, &conf->crl) != NGX_OK)
    {
        return NGX_CONF_ERROR;
    }

    if (ngx_ssl_dhparam(cf, &conf->ssl, &conf->dhparam) != NGX_OK)
    {
        return NGX_CONF_ERROR;
    }

    if (ngx_ssl_ecdh_curve(cf, &conf->ssl, &conf->ecdh_curve) != NGX_OK)
    {
        return NGX_CONF_ERROR;
    }

    ngx_conf_merge_value(conf->builtin_session_cache,
                         prev->builtin_session_cache, NGX_SSL_NONE_SCACHE);

    if (conf->shm_zone == NULL)
    {
        conf->shm_zone = prev->shm_zone;
    }

    if (ngx_ssl_session_cache(&conf->ssl, &ngx_http_ssl_sess_id_ctx,
                              conf->certificates, conf->builtin_session_cache,
                              conf->shm_zone, conf->session_timeout)
        != NGX_OK)
    {
        return NGX_CONF_ERROR;
    }

    ngx_conf_merge_value(conf->session_tickets, prev->session_tickets, 1);

#ifdef SSL_OP_NO_TICKET
    if (!conf->session_tickets)
    {
        SSL_CTX_set_options(conf->ssl.ctx, SSL_OP_NO_TICKET);
    }
#endif

    ngx_conf_merge_ptr_value(conf->session_ticket_keys,
                             prev->session_ticket_keys, NULL);

    if (ngx_ssl_session_ticket_keys(cf, &conf->ssl, conf->session_ticket_keys)
        != NGX_OK)
    {
        return NGX_CONF_ERROR;
    }

    if (conf->stapling)
    {
        if (ngx_ssl_stapling(cf, &conf->ssl, &conf->stapling_file,
                             &conf->stapling_responder, conf->stapling_verify)
            != NGX_OK)
        {
            return NGX_CONF_ERROR;
        }
    }

    if (ngx_ssl_early_data(cf, &conf->ssl, conf->early_data) != NGX_OK)
    {
        return NGX_CONF_ERROR;
    }

    return NGX_CONF_OK;
}


static ngx_int_t
ngx_http_ssl_compile_certificates(ngx_conf_t *cf, ngx_http_ssl_srv_conf_t *conf)
{
    ngx_str_t                       *cert, *key;
    ngx_uint_t                       i, nelts;
    ngx_http_complex_value_t        *cv;
    ngx_http_compile_complex_value_t ccv;

    cert  = conf->certificates->elts;
    key   = conf->certificate_keys->elts;
    nelts = conf->certificates->nelts;

    for (i = 0; i < nelts; i++)
    {
        if (ngx_http_script_variables_count(&cert[i]))
        {
            goto found;
        }

        if (ngx_http_script_variables_count(&key[i]))
        {
            goto found;
        }
    }

    return NGX_OK;

found:

    conf->certificate_values =
        ngx_array_create(cf->pool, nelts, sizeof(ngx_http_complex_value_t));
    if (conf->certificate_values == NULL)
    {
        return NGX_ERROR;
    }

    conf->certificate_key_values =
        ngx_array_create(cf->pool, nelts, sizeof(ngx_http_complex_value_t));
    if (conf->certificate_key_values == NULL)
    {
        return NGX_ERROR;
    }

    for (i = 0; i < nelts; i++)
    {
        cv = ngx_array_push(conf->certificate_values);
        if (cv == NULL)
        {
            return NGX_ERROR;
        }

        ngx_memzero(&ccv, sizeof(ngx_http_compile_complex_value_t));

        ccv.cf            = cf;
        ccv.value         = &cert[i];
        ccv.complex_value = cv;
        ccv.zero          = 1;

        if (ngx_http_compile_complex_value(&ccv) != NGX_OK)
        {
            return NGX_ERROR;
        }

        cv = ngx_array_push(conf->certificate_key_values);
        if (cv == NULL)
        {
            return NGX_ERROR;
        }

        ngx_memzero(&ccv, sizeof(ngx_http_compile_complex_value_t));

        ccv.cf            = cf;
        ccv.value         = &key[i];
        ccv.complex_value = cv;
        ccv.zero          = 1;

        if (ngx_http_compile_complex_value(&ccv) != NGX_OK)
        {
            return NGX_ERROR;
        }
    }

    conf->passwords = ngx_ssl_preserve_passwords(cf, conf->passwords);
    if (conf->passwords == NULL)
    {
        return NGX_ERROR;
    }

    return NGX_OK;
}


static char *
ngx_http_ssl_enable(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_http_ssl_srv_conf_t *sscf = conf;

    char *rv;

    rv = ngx_conf_set_flag_slot(cf, cmd, conf);

    if (rv != NGX_CONF_OK)
    {
        return rv;
    }

    sscf->file = cf->conf_file->file.name.data;
    sscf->line = cf->conf_file->line;

    return NGX_CONF_OK;
}

#if (NGX_HTTP_SSL && NGX_SSL_ASYNC)
static char *
ngx_http_ssl_enable_async(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_http_ssl_srv_conf_t *sscf = conf;
    char                    *rv;
    ngx_flag_t              *pssl, *pssl_async;

    rv = ngx_conf_set_flag_slot(cf, cmd, conf);

    if (rv != NGX_CONF_OK)
    {
        return rv;
    }

    /* If ssl_async on is configured, then ssl on is configured by default
     * This will align 'ssl_async on;' and 'listen port ssl' diretives
     * */
    pssl       = (ngx_flag_t *)((char *)conf
                          + offsetof(ngx_http_ssl_srv_conf_t, enable));
    pssl_async = (ngx_flag_t *)((char *)conf + cmd->offset);

    if (*pssl_async && *pssl != 1)
    {
        *pssl = *pssl_async;
    }

    sscf->file = cf->conf_file->file.name.data;
    sscf->line = cf->conf_file->line;

    return NGX_CONF_OK;
}
#endif

static char *
ngx_http_ssl_password_file(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_http_ssl_srv_conf_t *sscf = conf;

    ngx_str_t *value;

    if (sscf->passwords != NGX_CONF_UNSET_PTR)
    {
        return "is duplicate";
    }

    value = cf->args->elts;

    sscf->passwords = ngx_ssl_read_password_file(cf, &value[1]);

    if (sscf->passwords == NULL)
    {
        return NGX_CONF_ERROR;
    }

    return NGX_CONF_OK;
}


static char *
ngx_http_ssl_session_cache(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_http_ssl_srv_conf_t *sscf = conf;

    size_t     len;
    ngx_str_t *value, name, size;
    ngx_int_t  n;
    ngx_uint_t i, j;

    value = cf->args->elts;

    for (i = 1; i < cf->args->nelts; i++)
    {
        if (ngx_strcmp(value[i].data, "off") == 0)
        {
            sscf->builtin_session_cache = NGX_SSL_NO_SCACHE;
            continue;
        }

        if (ngx_strcmp(value[i].data, "none") == 0)
        {
            sscf->builtin_session_cache = NGX_SSL_NONE_SCACHE;
            continue;
        }

        if (ngx_strcmp(value[i].data, "builtin") == 0)
        {
            sscf->builtin_session_cache = NGX_SSL_DFLT_BUILTIN_SCACHE;
            continue;
        }

        if (value[i].len > sizeof("builtin:") - 1
            && ngx_strncmp(value[i].data, "builtin:", sizeof("builtin:") - 1)
                   == 0)
        {
            n = ngx_atoi(value[i].data + sizeof("builtin:") - 1,
                         value[i].len - (sizeof("builtin:") - 1));

            if (n == NGX_ERROR)
            {
                goto invalid;
            }

            sscf->builtin_session_cache = n;

            continue;
        }

        if (value[i].len > sizeof("shared:") - 1
            && ngx_strncmp(value[i].data, "shared:", sizeof("shared:") - 1)
                   == 0)
        {
            len = 0;

            for (j = sizeof("shared:") - 1; j < value[i].len; j++)
            {
                if (value[i].data[j] == ':')
                {
                    break;
                }

                len++;
            }

            if (len == 0)
            {
                goto invalid;
            }

            name.len  = len;
            name.data = value[i].data + sizeof("shared:") - 1;

            size.len  = value[i].len - j - 1;
            size.data = name.data + len + 1;

            n = ngx_parse_size(&size);

            if (n == NGX_ERROR)
            {
                goto invalid;
            }

            if (n < (ngx_int_t)(8 * ngx_pagesize))
            {
                ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                                   "session cache \"%V\" is too small",
                                   &value[i]);

                return NGX_CONF_ERROR;
            }

            sscf->shm_zone =
                ngx_shared_memory_add(cf, &name, n, &ngx_http_ssl_module);
            if (sscf->shm_zone == NULL)
            {
                return NGX_CONF_ERROR;
            }

            sscf->shm_zone->init = ngx_ssl_session_cache_init;

            continue;
        }

        goto invalid;
    }

    if (sscf->shm_zone && sscf->builtin_session_cache == NGX_CONF_UNSET)
    {
        sscf->builtin_session_cache = NGX_SSL_NO_BUILTIN_SCACHE;
    }

    return NGX_CONF_OK;

invalid:

    ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "invalid session cache \"%V\"",
                       &value[i]);

    return NGX_CONF_ERROR;
}


static ngx_int_t
ngx_http_ssl_init(ngx_conf_t *cf)
{
    ngx_uint_t                 a, p, s;
    ngx_http_conf_addr_t      *addr;
    ngx_http_conf_port_t      *port;
    ngx_http_ssl_srv_conf_t   *sscf;
    ngx_http_core_loc_conf_t  *clcf;
    ngx_http_core_srv_conf_t **cscfp, *cscf;
    ngx_http_core_main_conf_t *cmcf;

    cmcf  = ngx_http_conf_get_module_main_conf(cf, ngx_http_core_module);
    cscfp = cmcf->servers.elts;

    for (s = 0; s < cmcf->servers.nelts; s++)
    {
        sscf = cscfp[s]->ctx->srv_conf[ngx_http_ssl_module.ctx_index];

        if (sscf->ssl.ctx == NULL || !sscf->stapling)
        {
            continue;
        }

        clcf = cscfp[s]->ctx->loc_conf[ngx_http_core_module.ctx_index];

        if (ngx_ssl_stapling_resolver(cf, &sscf->ssl, clcf->resolver,
                                      clcf->resolver_timeout)
            != NGX_OK)
        {
            return NGX_ERROR;
        }
    }

    if (cmcf->ports == NULL)
    {
        return NGX_OK;
    }

    port = cmcf->ports->elts;
    for (p = 0; p < cmcf->ports->nelts; p++)
    {
        addr = port[p].addrs.elts;
        for (a = 0; a < port[p].addrs.nelts; a++)
        {
            if (!addr[a].opt.ssl)
            {
                continue;
            }

            cscf = addr[a].default_server;
            sscf = cscf->ctx->srv_conf[ngx_http_ssl_module.ctx_index];

            if (sscf->certificates == NULL)
            {
                ngx_log_error(NGX_LOG_EMERG, cf->log, 0,
                              "no \"ssl_certificate\" is defined for "
                              "the \"listen ... ssl\" directive in %s:%ui",
                              cscf->file_name, cscf->line);
                return NGX_ERROR;
            }
        }
    }

    return NGX_OK;
}
